Soreiyu
Freakconformist
I can't give you a lot of commentary on how to work 3D art.
You have a good grasp on using 3D perspective. It just seems to be a matter of practice and refining your technique.
I think the problem is more that I don't know how to pull small parts in order to make fingers and such without stretching more than what I need. It would probably be easier in a different program one where things are not molded.
My brother, who does work in 3D graphics used to use a program the used a mesh frame to create the form. (I get the basics of that, but I wouldn't be able to use it very well.)
I guess he started using Z-Brush about 4-5 years ago, which is supposed to be more like sculpting clay. It looks like the program you are using is more like that.
If this was the former program, I would say that you need to increase the amount of points in your grid. That would give you more surface area to manipulate and up the amount of detail you can use. (while also killing your computer's processor.)
I don't know if these Z-Brush type programs work on the same principal though.